Unsaturated hydrocarbons are a significant contaminant in ground water and a variety of industrial waste solutions. A large number of systems and methods have been proposed for reacting or otherwise eliminating various types of contaminants.
For example, in recent years UV-peroxide and ozone systems have become a treatment of preference for removal of toxic organics in waste water because such systems chemically convert contaminant species to benign components. Published PCT application PCT/US94/07983, in which applicant is an inventor and which is hereby incorporated by reference, discloses systems in which hydrogen peroxide is added to the waste solution and is subjected to ultraviolet irradiation either before or after it is so added, and in which the waste is treated in a reactor coated with a photocatalyst such as titanium oxide.
However, hydrogen peroxide is relatively expensive, the cost becomes a significant consideration particularly as contaminant concentrations increase. Further, the rate of contaminant oxidation depends on the ability of peroxide to absorb UV light and to dissociate into hydroxyl radicals. UV light intensity diminishes with distance from the light source, and reactor size thus has been limited since reactors with radii larger than a critical dimension to not achieve their decontamination goals.
There remains a need for less expensive systems that can treat greater volumes of waste water containing higher concentrations of hydrocarbon waste.